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Preservation

Derby Owners Club is not lost

A linked-cabinet Sega arcade game with no official way left to play it, kept running by the people who remember it. Here is what was saved, what it took, and what is still missing.

A lit row of Derby Owners Club seats with people playing, the main race board glowing at the end.
A full row, lit and running, with people in the seats. This is what was nearly lost.

The game

Derby Owners Club arrived in arcades in 1999. You raised a racehorse: fed it, trained it, named it, and carried it home on a magnetic card so it would still be yours next week. Then you sat down in a row of linked seats and raced it on a shared screen the size of a doorway. Cabinets shipped in four-, six- and eight-player variants, so a full eight-seat row meant seven other people riding against you at once, each at their own satellite.

It never got a console port. There were two attempts to bring it home, both Japan only and both online services rather than games you could own: Derby Owners Club Online on PC in 2004, and Derby Owners Club -Next Furlong- on phones in 2012. Sega switched the PC servers off in 2006 and the mobile ones in January 2019. So every official way to play this game, in an arcade or at home, has now been turned off. When the cabinets left the arcades, the horses on those cards had nowhere left to run.

1999Arcade release
NoneConsole port
4·6·8Seat variants
4Versions running

They arrived like this

Seven complete Derby Owners Club setups live here: two full eight-seat rows, two full four-seat rows, a four-player streaming rig, and two more built up from the parts without their cabinets. An eight-seat row alone is ten boards once you count the main unit properly, so that is a lot of Sega hardware in one building.

It came the way most surviving arcade hardware does: on a truck, in pieces, having sat somewhere dark for a decade.

A row of Derby Owners Club satellite player seats in a garage, March 2019.
Player seats in the garage, March 2019.
A Derby Owners Club satellite cabinet opened up, showing its monitor, boards and wiring.
A seat with its panels off. Every one of these had to come apart before it could go back together.

The hardware

Derby Owners Club is not one machine. A main unit drives the two-screen race board, and each player seat is a separate arcade board on a network link. A full eight-player row is ten boards behaving as one, because the main unit is itself a stack of two. They all have to agree on the same race, frame by frame, or the row does not run at all. Sega sold it in four-, six- and eight-seat configurations, and each one links differently.

That is the part that kept it out of reach. Getting a full row to boot, link and stay in sync meant learning how the master hands out seats, why a satellite that joins late is refused, and what the mesh does when one board drops. A single cabinet is an emulation problem; a linked row is a networking problem wearing a cabinet costume.

More on the hardware and keeping it running →

Four monitors running Derby Owners Club above a rack of linked Sega NAOMI arcade boards.
Sega NAOMI boards, linked and running on a bench. This is what a race looks like before it reaches a cabinet.
A home rig: two player seats with arcade control panels and card readers, the two-screen race board between them, horse cards on the desk, arcade boards racked below.
The whole game on one desk: two seats with their control panels, the race board between them, horse cards waiting, and the boards doing the work underneath.

The software

A horse lives on a magnetic stripe as a few hundred bytes. Nothing about that layout was documented, so every byte had to be worked out by hand: stats, coat, pedigree, running style, and the record of every race it has ever run.

That map is what makes a saved horse portable at all, and it is published openly, along with the tools built on top of it: card readers and differs, breeding and feeding advisors, roster and track browsers. It is the manual the game never shipped with.

The Japanese releases needed their own pass. Their cards use a different marker and store kana names in fixed slots, so a World-Edition reader simply refuses them. Decoding that is what brought the Japanese versions back alongside the World ones.

Japanese players had already worked out much of how this game behaves, years before anyone could read the ROM. Their sites are mostly gone now. What the Japanese community knew → collects that work, in both languages, with each claim marked according to whether the ROM bears it out.

Physical Derby Owners Club horse cards on an arcade control panel, with the Japanese card service menu on screen.
Real horse cards on the panel, with the Japanese card menu on screen. Each card is a horse somebody raised.

Where the preservation actually stands

Four versions are preserved, running, and able to read and write their own cards: the two World Edition revisions and both Japanese releases.

World Rev CWorld Rev DDOC 2000DOC '99
Program ROMepr-22336cepr-22336depr-22284aepr-22099b
Horse record32-byte32-byte32-byte28-byte
Roster records244244244244
Card formatdecodeddecodeddecodeddecoded
Runs + saves homeyesyesyesyes

Every row above was read out of the ROM bytes and re-checked independently, not taken from documentation. Rev C and Rev D turn out to be byte-identical across all 244 roster records, which settles a long-running argument about whether the later revision quietly changed the horses. It did not.

The hardwareTen boards behaving as one, and what it takes to keep them running. The softwareReading a horse out of a few hundred bytes. Play it onlineReal cabinets, streamed, with seats you can take. Myths, testedCommunity claims checked against the ROM. Claim, evidence, verdict. What the Japanese community knewA bilingual archive of what Japanese players worked out between 1999 and 2001, recovered from dead fan sites and checked against the ROM. What the English community knewThe export game's own record: handbooks, fan sites and Sega's English paperwork, recovered from the Wayback Machine and the community's own files.
The two-screen race board showing a zebra-coated horse winning with a new track record.
A zebra-coated horse taking a new track record. The coat is a rare variant selected by a single byte, one of many things nobody had written down until somebody went looking.

What we still do not know

The honest part. Some of this needs hardware nobody has been able to put in front of it yet, and if you can help with any of it, we would like to hear from you.

Where we draw the line

Derby Owners Club is still Sega's. Nothing on this site distributes the game.

The Host Pack set cabinets up and linked them together, then pointed at game files that you provide. We do not host them, mirror them, or help anyone find them, and we are not going to start. That is a deliberate choice, not an oversight. We stopped handing the pack out in August 2026.

If Sega ever brings Derby Owners Club back, buy it. An official release would be better than anything we have built here, and we would say so loudly.

Racing is free and always has been: no ads, and nothing that decides a race behind a paywall. Running the servers and the machines costs real money, and what members chip in is what covers it. What members pay for is software we wrote ourselves, never Sega's game.

Why bother

Derby Owners Club is a strange, wonderful, nearly-lost arcade game. Getting it running again, with the linked satellite cabinets and all, took a lot of reverse-engineering and stubborn tinkering. It is shared so other fans can experience it again, the way we remember it.

There are people in our Discord who last played this in a mall twenty years ago and assumed they never would again. That is the entire point.

Ride on.
John

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